DESCRIPTION: (after application) Upper respiratory infections (URIs) are a leading cause of acute visits to pediatric providers, and the majority of children presenting with URIs are likely to receive antibiotics, either with or without a concurrent bacterial diagnosis. One large study has found that almost 50 percent of children with URIs are inappropriately treated with antibiotics. This likely underestimates the true degree of unnecessary antibiotic use since physicians may ascribe non-specific symptoms to bacterial etiologies (e.g., by diagnosing sinusitis in the setting of cold symptoms) so as to justify their use of antibiotics. Although fewer than 20 percent of children who visit physicians for URIs meet criteria for bacterial sinusitis, as many as 50-70 percent may be diagnosed with sinusitis and given antibiotics. Such overuse of antibiotics increases antibiotic resistance, increases medical costs, and increases risk for antibiotic-associated adverse events. Unfortunately, changing physician behavior has proven to be difficult and costly. Clinical practice guidelines have not been well received by providers. Continuing medical education is largely ineffective. Academic detailing is marginally effective but is labor-intensive. Importantly, it is not that physicians do not welcome guidance in clinical decision-making but, rather, that many current and past efforts have failed to meet their expectations. Providers are in search of, and in need of, pertinent and helpful evidence-based solutions that do not increase their workload. This application involves testing the ability of diagnostic decision aid to improve the diagnostic accuracy of sinusitis. The investigator will seek to determine if use of a diagnostic decision aid (DDA), that is completed by parents in the waiting room prior to being seen, can assist providers in more accurately diagnosing sinusitis, thereby diminishing inappropriate antibiotic use. The applicant proposes to conduct a randomized controlled trial using wireless hand-held computers in a university-based clinic. This setting will answer important complementary questions. First, can a DDA prove useful to providers? Second, can it be integrated into a wireless, computerized clinical information system?